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arXiv · 2301.11373

Magnetic, Optoelectronic, and Rietveld refined structural properties of Al3+ substituted nanocrystalline Ni-Cu spinel ferrites: An experimental and DFT based study

N. Hasan·S. S. Nishat·S. Sadman·M. R. Shaown·M. A. Hoquee·M. Arifuzzaman·A. Kabir
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Abstract

The nanocrystalline Ni0.7Cu0.3AlxFe2-xO4 (x=0.00: 0.02: 0.10) is prepared through the sol-gel autocombustion route.Both XRD and Rietveld confirm the single-phase cubic spinel structure of the investigated materials.Other structural parameters refined by the Rietveld refinement analysis are corroborated to single-phase cubic spinel formation of the NPs.Leveraging a vibrating sample magnetometer (VSM) the consequence of Al3+ substitution on the magnetic parameters is studied.The saturation magnetization (MS) and Bohr magneton are found to decrease with Al3+ substitution.The Remanence ratio and coercivity (HC) are observed to be very low suggesting the materials are soft ferromagnetic.First-principle calculations were carried out using the density functional theory (DFT) to demonstrate the optoelectronic behavior of the materials.The electronic bandgap is found low as Eg=2.99eV for the explored materials with observing defect states at 0.62eV.The optoelectronic properties of Al3+ substituted Ni-Cu ferrite NPs have been characterized through the DFT simulation for the first time, demonstrating their potentiality for optoelectronic device applications.The materials' optical anisotropy is observed along the x-axis, which manifests their tunability through light-matter interaction.

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N. Hasan, S. S. Nishat, S. Sadman, M. R. Shaown, M. A. Hoquee, M. Arifuzzaman, A. Kabir. 2023-01-26. Magnetic, Optoelectronic, and Rietveld refined structural properties of Al3+ substituted nanocrystalline Ni-Cu spinel ferrites: An experimental and DFT based study. https://doi.org/10.1016/j.jmmm.2023.170675

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